1. Field of the Invention
The present invention relates to a disk brake and a sliding member.
2. Description of the Related Art
In a piston for a disk brake that is the example of a sliding member in which to be slidably moved in a cylinder, it is known that a chromium plating layer is formed on the sliding surface so as to minimize sliding resistance between the piston and a piston seal. Due to the formation of the chromium plating layer, brake feeling can be improved. See, for example, a Japanese Patent Application Laid-open No. 2006-292119 (hereinafter to be referred to as Patent Document). In conventional art, for this kind of the piston where a piston base body is made of aluminum alloy, in order to provide the disk-brake piston that secures thermal shock resistance and corrosion resistance, it was necessary to form an iron plating layer as groundwork of the chromium plating layer. In case that the iron plating layer is formed on the piston base body that is made of the aluminum alloy, a zinc immersion process needs to be conducted at twice for pretreatment removing oxide films on the surface of the piston base body completely. Accordingly, surface processes would be complicated.
As explained hereinabove, in the above prior art, production of the disk brake and the sliding member becomes bothersome. Accordingly, the present invention is made in light of the above problem, and it is an object of the present invention to provide a disk brake and a sliding member that can be easily produced.